Perhaps you should try some spelling variations:
model studies » model study
filosofia le » filosofia de, filosofia del, filosofia da
filosofia e » filosofia de, filosofia del
studies la » studies lab, studies lca, studies lia
roi model » roi models

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: roi model studies la ((filosofia le) OR (filosofia e)) literatura.
• Adding a wildcard symbol may retrieve word variants: roi model studies la ((filosofia le) or (filosofia e)) literatura*.